Hetero-bimetallic paddlewheel complexes for enhanced CO reduction selectivity in MOFs: a first principles study.

The reduction of carbon dioxide (CO) into value-added feedstock materials, fine chemicals, and fuels represents a crucial approach for meeting contemporary chemical demands while reducing dependence on petrochemical sources. Optimizing catalysts for the CO reduction reaction (CORR) can entail employing first principles methodology to identify catalysts possessing desirable attributes, including the ability to form diverse products or selectively produce a limited set of products, or exhibit favorable reaction kinetics. In this study, we investigate CORR on bimetallic Cu-based paddlewheel complexes, aiming to understand the impact metal substitution with Mn(II), Co(II), or Ni(II) has on bimetallic paddlewheel metal-organic frameworks.

High Accuracy Potential Energy Curves and Dipole Moment Functions for the Σ and Π Spin States of the CF Diatomic Molecule.

Potential energy curves and dipole moment functions constructed using high-accuracy methods allow for an in-depth examination of the electronic structure of diatomic molecules. computations serve as a valuable complement to experimental data, offering insights into the nature of short-lived molecules such as those encountered within the interstellar medium (ISM). While laboratory experiments provide critical groundwork, the ISM's conditions often permit longer lifetimes for lower stability molecules, enabling unique observations.

Catalyst Engineering for the Selective Reduction of CO to CH : A First-Principles Study on X-MOF-74 (X=Mg, Mn, Fe, Co, Ni, Cu, Zn).

The conversion of carbon dioxide (CO ) into more valuable chemical compounds represents a critical objective for addressing environmental challenges and advancing sustainable energy sources. The CO reduction reaction (CO RR) holds promise for transforming CO into versatile feedstock materials and fuels. Leveraging first-principles methodologies provides a robust approach to evaluate catalysts and steer experimental efforts.

Multivariate Flexible Framework with High Usable Hydrogen Capacity in a Reduced Pressure Swing Process.

Step-shaped adsorption-desorption of gaseous payloads by flexible metal-organic frameworks can facilitate the delivery of large usable capacities with significantly reduced energetic penalties. This is desirable for the storage, transport, and delivery of H, as prototypical adsorbents require large swings in pressure and temperature to achieve usable capacities approaching their total capacities. However, the weak physisorption of H typically necessitates undesirably high pressures to induce the framework phase change.

A PEGylated Tin Porphyrin Complex for Electrocatalytic Proton Reduction: Mechanistic Insights into Main-Group-Element Catalysis.

Electrocatalytic proton reduction to form dihydrogen (H ) is an effective way to store energy in the form of chemical bonds. In this study, we validate the applicability of a main-group-element-based tin porphyrin complex as an effective molecular electrocatalyst for proton reduction. A PEGylated Sn porphyrin complex (SnPEGP) displayed high activity (-4.

Electrocatalytic Hydrogen Evolution Using A Molecular Antimony Complex under Aqueous Conditions: An Experimental and Computational Study on Main-Group Element Catalysis.

Electrocatalytic hydrogen gas production is considered a potential pathway towards carbon-neutral energy sources. However, the development of this technology is hindered by the lack of efficient, cost-effective, and environmentally benign catalysts. In this study, a main-group-element-based electrocatalyst, SbSalen, is reported to catalyze the hydrogen evolution reaction (HER) in an aqueous medium.

High accuracy ab initio potential energy surface for the HO-H van der Waals dimer.

A representation of the three-dimensional potential energy surface (PES) of the HO-H van der Waals dimer is presented. The HO molecule is treated as a rigid body held at its experimentally determined equilibrium geometry, with the OH bond length set to 1.809 650 34 a and the HOH bond angle set to 1.

Direct Identification of Mixed-Metal Centers in Metal-Organic Frameworks: Cu(BTC) Transmetalated with Rh Ions.

Raman spectroscopy was used to establish direct evidence of heterometallic metal centers in a metal-organic framework (MOF). The Cu(BTC) MOF HKUST-1 (BTC = benzenetricarboxylate) was transmetalated by heating it in a solution of RhCl to substitute Rh ions for Cu ions in the dinuclear paddlewheel nodes of the framework. In addition to the Cu-Cu and Rh-Rh stretching modes, Raman spectra of (CuRh)(BTC) show the Cu-Rh stretching mode, indicating that mixed-metal Cu-Rh nodes are formed after transmetalation.

Selecting Quantum-Chemical Methods for Lanthanide-Containing Molecules: A Balance between Accuracy and Efficiency.

An analysis of how different density functionals, basis sets, and relativistic approximations affect the computed properties of lanthanide-containing molecules allows one to determine which method provides the highest accuracy. Historically, many different density functional methods have been employed to perform calculations on lanthanide complexes and so herein is a detailed analysis of how different methodological combinations change the computed properties of three different families of lanthanide-bearing species: lanthanide diatomic molecules (fluorides and oxides) and their dissociation energies; larger, molecular complexes and their geometries; and lanthanide bis(2-ethylhexyl)phosphate structures and their separation free energies among the lanthanide series. The B3LYP/Sapporo/Douglas-Kroll-Hess (DKH) method was shown to most accurately reproduce dissociation energies calculated at the CCSDT(Q) level of theory with a mean absolute deviation of 1.